Examples for 8th grade - page 3

  1. Diagonal
    rectangle_diagonal Calculate the length of the diagonal of the rectangle ABCD with sides a = 7 cm, b = 6 cm.
  2. Ladder
    rebrik_1 Ladder 5 m long is leaning against the wall. It foot is 0.9 m away from the wall. In which height ladder touch the wall?
  3. Chickens and rabbits
    pipky In the yard were chickens and rabbits. They had 44 heads and 124 legs. How many chickens and how many rabbits was in the yard?
  4. Saving
    cars Kevin save € 4620 to buy a car. Yet it lacks save 65% of the car price. How much is the car?
  5. Tractors
    tractors Fields go plow two tractors with various performance. The first tractor plow whole field in 5 hours, the second tractor plow whole field 5 hours longer. How long take plow whole field with two tractors?
  6. Number
    sqrt_2 Is number 4.764023 irrational?
  7. Segments
    abs Which of the pairs of numbers on the number line encloses the longest segment: ?
  8. Seedcake
    pletenky Seedcake costs 50 cents. How many minimum seedcakes we must buy that we can pay in cash only whole euros?
  9. Drunk man
    drunk-man Drunkman has 2.1‰ of alcohol in the blood. How many grams of alcohol has in blood, if he have 6 kg of blood?
  10. Density - simple example
    mercury Material of density of 1278 kg/m3 occupies a container volume of 80 cm3. What is its mass?
  11. Time
    time Write time in minutes rounded to one decimal place: 1 h 42 m 22 s.
  12. Road repair
    workers_1 Road repair took 16 days for 34 workers if they worked 6 hours a day. How many days take repair same road 33 workers if they work 6 per day?
  13. Mr Novak
    Salary-increase Mr Novak earns an average 638 euros. When increasing the salary they gave him a choice: ? What is better choice for Mr Novak?
  14. Monkey
    monkey Monkey fell in 31 m deep well. Every day her scramble 3 meters, at night dropped back by 2 m. On that day it gets hangover from the well?
  15. Railways
    railways Railways climb 5.8 ‰. Calculate the height difference between two points on the railway distant 2389 meters.
  16. Tournament
    turnaj Determine how many ways can be chosen four representatives from 27 students to school tournament.
  17. Sprayers
    postrekovac The vineyard can be sprayed first sprayer in 5 hours and with the second in 7 hours. How long would it take if we use sprayers both at once?
  18. Vinegar 2
    ocet How many percentage of getvinegar solution, if we mix to 14.5 liters of 7.8% and 2.5 liters of 5.8% vinegar?
  19. Discount
    pulover Ladies sweater was twice discounted. First by 17%, then by 17% of the new price. Its final price was 72 USD. Determine the original price of sweater.
  20. Team
    football The football team has 11 players. Their average age is 21 years. During the match due to injury, one player withdraws and the average age of the team is 20. How old was injured player?

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